Introduction

Since Jan. 1, 2015, The Washington Post has been compiling a database of every fatal shooting in the US by a police officer in the line of duty.

While there are many challenges regarding data collection and reporting, The Washington Post has been tracking more than a dozen details about each killing. This includes the race, age and gender of the deceased, whether the person was armed, and whether the victim was experiencing a mental-health crisis. The Washington Post has gathered this supplemental information from law enforcement websites, local new reports, social media, and by monitoring independent databases such as "Killed by police" and "Fatal Encounters". The Post has also conducted additional reporting in many cases.

There is additional dataset of US census data on racial demographics. Source of census data.

The objective of this analysis is to support the arguments that police officers are racialy biased and I hope it will provide thoughtful, fact-based analysis of this important issue.

The orginal The Washington Post's analysis here.

Importing and Loading Data

Data Cleaning

Share of Race by City

We have 20 cities with missing values for race shares. We could find missing information, but for now we just keep it in mind during analysis.

Fatalities Dataset

We have some missing values for the name, armed, age, race, flee, long and lat columns. We just keep it in mind doing particular data exploration. We also convert the capital letter symbols for race to a particular full name of the race.

Creating separate dataframe for racial profile of USA

Source : Historical racial and ethnic demographics of the USA)

Let's do some initial analysis.

EDA

Comparing the Total Number of Deaths of Men and Women

How Old Were the People Killed?

Percentage of people killed under 30 years old.

Insights:

Were People Armed?

Insights:

Race of killed people

CHI-SQUARE TEST

Chi-square test provides a way to investigate differences in the distributions of categorical variables with the same categories and dependence between categorical variables. Let's examine if there is a difference between distribution of race in fatal police shootings and the distribution of race in the US population.

Insights:

One might argue, that the higher proportion of black pleople killed is simply because there are more black people in the particular area in general. Let' s examine this statement.

Bar Chart Showing the Racial Makeup of US States with most % of black people

Insights:

Choropleth map of police killings

Insights:

Number of Police Killings Over Time

For possible missing data we excluded last 2 months from the dataset.

Insights:

Epilogue

People have been shot and killed in encounters with officers even if they were unarmed or carrying a toy weapon. Such killings seem very unnecessary, but further understanding and investigation is required. Every time an officer shoots a person belonging to the minority, it does not necessarily mean racial bias. But, as our analysis showed, bias is not absent. In recent years, the fact that police officers could be racially biased was the primary motivation for the creation of the socially relevant and internationally discussed #BlackLivesMatter movement. We see it as a starting point to understand the truth behind possible racial bias in the population in general.

© 2021 Miroslava Ježíková